A method using a closed squeegee head has hitherto been known as a screen printing method of printing a substrate with paste, like cream solder and conductive paste, in an electronic component mounting step. Under the method, as opposed to normal screen printing in which paste is fed directly over a mask plate, paste in a squeegee head is pressurized while the squeegee head with internally stored paste is held in contact with a mask plate.
The paste is thereby squeezed into pattern holes of the mask plate by a paste contact surface provided on a lower surface of the squeegee head. The squeegee head is then slid over the mask plate, thereby sequentially filling the respective pattern holes with the paste (see; for instance, Patent Document 1). In the example described in connection with the patent document, the squeegee head is separated into an upper portion including a cartridge that stores the paste and a lower portion including a printing space where the pressurized paste is brought into contact with the mask plate. The upper portion is reclosable while axially fastened to the lower portion.